From hollywoodreporter.com:

Fox is launching its first networkwide public service campaign in two years: “Green It. Mean It.”

Timed to lead up to Earth Day on April 22, the weeklong eco-themed campaign starts today and includes on- and off-air elements including promos starring Fox talent.

Omar Epps and Lisa Edelstein from “House,” Emily Deschanel from “Bones” and Kelsey Grammer and Fred Willard from “Back to You” are among those who will offer “green tips” to viewers, and Fox affiliates are offered an “Are You Smart Enough to Save the Planet?” promotion to drive tune-in for a special two-hour “Are You Smarter Than a 5th Grader?”

The efforts represent the first on-air public service campaign for Fox since the 2006 PAUSE campaign, which promoted making smart choices to teenagers. That campaign was done as part of an partnership with the Kaiser Foundation; the “Green It. Mean It.” campaign was finalizing a deal with an advertiser.

In November, NBC became the first broadcast network to do a “green week” of programming and marketing tie-ins. Last year, Fox parent News Corp. embraced promoting ecological initiatives after owner Rupert Murdoch announced his intention to educate his company’s viewers and readers about global warming.